1. Field of the Invention
The present invention relates to commercial manufacturing processes, and more particularly to hold routing management for commercial manufacturing processes.
2. Description of the Related Art
Large-scale manufacturing systems typically involve complex distributed supply and demand networks. A manufacturing facility generally includes a large number of production lines producing many products having multiple process steps and process sequences in manufacturing the final product. Changes in market supply and demand can cause a great deal of uncertainty in production demand, and purchase orders frequently may need to be halted, changed or rescheduled. If the order cannot be halted, rescheduled or updated methodically in a timely fashion, delays in production can occur.
For various reasons, a manufacturer may desire to temporarily stop the manufacturing process on a subset of products being produced. Quality concerns are one example, wherein ad hoc quality assurance checks are performed at certain points in a process. Another example is a scenario where products are manufactured prior to having the signoffs necessary before shipping a product to the customer. When these incidents occur, it is often necessary to hold product orders at a strategic point part-way through the manufacturing process. (Note that a work unit refers to an incomplete product undergoing manufacturing wherein the work unit may refer to one part of a larger whole.) If a work unit is not progressed to this point, the customer shipment dates may be missed and expected revenue from the products may dwindle. If a work unit is allowed to move beyond this point, the final products may require re-working, thereby creating extra workload and delays in shipment. Allowing work units to move beyond a strategic point may also increase the possibility that a final product may inadvertently ship without receiving the required re-work.
Yet another example of why a manufacturer may desire to temporarily stop the manufacturing process on a subset of products being produced is an unannounced product. In cases of an unannounced product, the manufacturer may wish to pre-build the product in anticipation of the announcement of the new product. Consequently, a hold must be placed on the new product to prevent shipment prior to the announced product availability date.
Conventional automated solutions simply halt the continuation of a work unit through manufacturing for any and all its process sequences. This approach stops all work in progress on a work unit at the exact location and time when the halt is issued, whether the work unit is in the build phase, test phase, clean and claim phase, etc. Therefore, the above approach does not allow for strategic start and stop of manufacturing at future positions in the manufacturing process. This prevents manufacturing from completing as much of the process as possible for the given circumstances, thereby jeopardizing customer shipments and company revenue. Further, the conventional automated solutions operate at a complete customer order level rather then discrete work unit levels. Consequently, when such a hold is placed, all work units associated with the customer order are stopped at their current routing, even if it is not necessary.
Another approach to this problem includes manual intervention, which involves an individual dealing with each individual work unit going through the manufacturing process. This approach is labor intensive, involving analysis to select which work units must be halted, locating and marking the identified work units, and forcing a stop of the manufacturing process at the appropriate time on the individual work units. This highlights the need for a system whereby it is noted which units have been halted and why each unit has been halted. This would help to discern between multiple work units which have been halted for different reasons.
The above labor-intensive approach is also prone to error. Orders can be accidentally overlooked, and there is not a way to query which work units have been held in process. This approach is further time intensive, creating the potential for inadvertent shipments of incorrect products. While working through a list of affected work units, those work units not immediately addressed will continue to move through the manufacturing process and could inadvertently ship without a required rework or signoff. Inadvertent shipping of a work unit may occur because the conventional approach does not allow for halting future activities.